Discussion :: Boats and Streams

A boat takes a total time of three hours to travel downstream from P and Q and upstream back from Q to P. What is the speed of the boat in still water?
I . The speed of the river current is 1 km per hour.
II.The distance between P and Q is 4 km.
A.
I alone sufficient while II alone not sufficient to answer 
B.
II alone sufficient while I alone not sufficient to answer 
C.
Either I or II alone sufficient to answer 
D.
Both I and II are not sufficient to answer 
E.
Both I and II are necessary to answer 
Answer : Option E
Explanation :
I. Speed of the current = 1 km/hr.
II. PQ = 4 km.
Let the speed of the boat in still water be x km/hr. Then,
\( \frac { 4 } { (X+1 )} +\)\( \frac { 4 } { (X1 )}=3\)This gives x.
Be The First To Comment